In order to conserve energy, Federal and State commercial and residential codes and regulations specify efficiency standards, included in these standards for piping, duct and associated equipment are insulation efficiency values. Insulation type, dimensions, hardware etc., can be specified. In addition, there is a need to protect all end edges of the insulation circumferentially projecting around such piping and associated equipment, usually by metallic caps.
As far as I am aware, most metallic caps for use in the aforementioned applications, are individually crafted, by conventional cutting, rolling and crimping techniques. While there has been some attempt to use factory fabrication methods, experience has shown that the side wall and top wall of such caps are still individually constructed in sequence and then united along full circumferential connection equi-spaced from the longitudinal axis of symmetry thereof, viz., to the circumferential extending termini of the top and side wall. Because of haphazard dimensional restrictions, there is required a doubled wall-overlap crimping arrangement ("Pittsburgh Seam") to unit the walls. Thus, such caps are expensive and because of dimensional instability, are subject to a need to continually retrofit the finished caps until a good fit occurs at the work site, all costly and time consuming operations.